The invention relates to a toothbrush having an exchangeable bristle plate.
Toothbrushes having an exchangeable bristle section are suitable in view of the growing awareness of hygiene and environmental matters. Every year vast quantities of toothbrushes are used up, and the numbers are increasing, it being the intention for the user to change the toothbrush every 2 to 3 months. This is necessary from the point of view of hygiene, It is not necessary, however, to throw away the entire toothbrush.
Help is provided here by the so-called exchangeable-head toothbrushes, in which it is only the bristle head which is replaced, the brush handle being retained. Such a toothbrush is known from G 85 25 867.9, in which a handle part is connected releasably to a brush part of predetermined length in order that the entire bristle region is supported over the entire surface area by a connector region of the handle part. For a press fit with just one groove/tongue connection in the form of a pin extension, provision is made for an extension on the handle part to be undercut and of angled design, with the result that the bristle part is secured in a positively locking manner, by way of an appropriately shaped end, against lateral displacement and lifting. In order to release the connection, a slot-like recess is made in the end side, and a tool can be introduced therein.
It has proven disadvantageous, however, that the design involves excessive outlay in order for the bristle section to be fastened securely, with the result that, in order to release the connection, additional tools are necessary or it is necessary to provide dedicated design elements in order to release the connection.
DE 44 34 617 A1 discloses a toothbrush having an exchangeable bristle insert which is received with latching action in an elongate retaining cutout of a head part. Latching strips on the circumferential surface of the bristle insert engage in latching grooves of the head part. The bristle insert tapers, in plan view, from one end to its other end and has smooth, uninterrupted sections of its circumferential surface butting flat against smooth, uninterrupted sections of the inner wall, this resulting in a wedge or clamping action of the bristle insert in the longitudinal direction. In the case of this previously known toothbrush, during the exchanging operation, the bristle plate is pressed out of the latching connection by virtue of pressure being applied to a push knob. The action of releasing such a latching connection is generally laborious and is thus disadvantageous in handling terms.
The object of the invention is thus to provide a toothbrush which hat an exchangeable bristle plate and allows, on the one hand, secure fastening of the bristle plate on a toothbrush body and, on the other hand, straightforward exchange of the bristle plate.
This object is achieved by the features of claim 1.
This provides a toothbrush which has an exchangeable bristle plate and allows the bristle plate to be anchored such that it is secured against offset positioning on the carrier plate of an otherwise unchanged toothbrush and, in the process, is very straightforward to handle and to release. It is only a small proportion of the overall material of the toothbrush which is exchanged. The round-wedge-form undercut, in which the round wedge of the bristle plate finally engages, precludes any possibility of offset positioning in the upward direction. It is not possible either for the bristle plate to be pushed out upward by virtue of pressure being applied on the central locking arrangement. In conjunction with the elongate central locking arrangement, any capacity for lateral displacement is prevented, with the result that the bristle plate is anchored firmly in captive fashion. The decisive factor, however, is that said fixed anchoring arrangement can easily be released by bending, as a result of which the undercut opens.
It has proven advantageous in this respect if the undercut decreases in size in each case in the outward direction from the inside in order, during the bending operation, to aid the release of the engagement of the shape-adapted end of the bristle plate.
The material used for the toothbrush body is preferably plastic, such as polypropylene (PP), polyethylene terephthalate (PET) or polyethylene terephthalate which is suitable for injection molding (PETG). This material is sufficiently flexible, which is advantageous for the exchange function and for the use of the toothbrush.
Further configurations of the invention can be gathered from the following description and the subclaims.